print("hello 皮皮虾")
name = "pipixia"
hello = "hello %s %s" % (name, "haha")
#占位符用在字符串内，%s是字符串，%d是整数，%f是小数，引号后加%，再用（定义字符串和数字），只有一个占位符不需要括号
print(hello)
hello = "hello" + name
print(hello)
a = input("输入a:")
a = int(a)
if a > 3:
    print("a>3")
else:
    print("a<=3")

